A system and an approach for determining various flows in an internal combustion engine, such as an amount of recirculation exhaust gas flow through a controlled valve and a fresh air mass flow to an intake of an engine. Also, among the sensors accommodated in the system, is an inexpensive but slow-responding lambda sensor in the exhaust stream.

Due to changes in a flow of an air-fuel mixture in a cylinder, reliable ignition due to spark discharge may not be possible. Therefore, an ignition control unit 24 includes a secondary voltage calculation unit 31 that calculates an average value of a secondary voltage generated on a secondary side of an ignition coil, an irregular flow ratio calculation unit 32 that calculates a ratio of cycles in which the average value of the secondary voltage is equal to or less than a set average value with respect to a cycle of the internal combustion engine in a predetermined period as an irregular flow ratio indicating that the flow of the air-fuel mixture in the cylinder is irregular, and an ignition operation amount correction unit 37 that corrects an ignition operation amount so that the irregular flow ratio is equal to or less than the set ratio value that is the target to be reached of the irregular flow ratio.

Electronic fuel injection for an internal combustion engine maintains an operator-specified air-to-fuel ratio during engine operations in high-speed, high-volume, mixed fuel applications. A microprocessor-based controller executes a program stored in memory to calculate a fuel flow value as a function of the specified air-to-fuel ratio and specified density ratio of mixed fuels. The controller outputs a control signal to a variable fuel flow relief valve and receives feedback from an engine fuel flow sensor. The controller adjusts the control signal until the feedback matches the fuel flow value. The program optimizes the fuel flow value by accounting for engine air flow, water vapor density, and dry air density effects in the calculation, based on signals received by the controller from various environmental sensors. The system has particular application in dragster engines that burn a mixture of nitromethane and methanol.

The disclosure provides a supercharging pressure control device for an internal combustion engine that may suppress misfires of the internal combustion engine caused by a large amount of condensed water and freezing of an intercooler and suppress the decrease in supercharging response under the conditions that such problems are unlikely to occur. The supercharging pressure control device for the internal combustion engine includes a supercharger (turbocharger), an intercooler, a supercharging pressure control part controlling a supercharging pressure based on a target supercharging pressure, and an intake air temperature acquisition part (intake air temperature sensor) acquiring a temperature of the intake air as an intake air temperature, and executes a supercharging pressure reduction control when the intake air temperature is greater than or equal to a specified first threshold temperature or less than or equal to a specified second threshold temperature less than the first threshold temperature.

Methods and systems are provided for mitigating water ingestion in a variable displacement engine. In one example, a method for a vehicle may comprise: with an engine of the vehicle turned on, responsive to detection of a water wading condition through which the vehicle is passing, operating the engine in a variable displacement engine (VDE) mode with a reduced number of cylinders of the engine activated and any cylinders in excess of the reduced number of cylinders deactivated. In this way, water ingestion into the cylinders of the engine and the resulting combustion instability may be avoided during the water wading conditions.

Due to changes in a flow of an air-fuel mixture in a cylinder, reliable ignition due to spark discharge may not be possible. Therefore, an ignition control unit 24 includes a secondary voltage calculation unit 31 that calculates an average value of a secondary voltage generated on a secondary side of an ignition coil, an irregular flow ratio calculation unit 32 that calculates a ratio of cycles in which the average value of the secondary voltage is equal to or less than a set average value with respect to a cycle of the internal combustion engine in a predetermined period as an irregular flow ratio indicating that the flow of the air-fuel mixture in the cylinder is irregular, and an ignition operation amount correction unit 37 that corrects an ignition operation amount so that the irregular flow ratio is equal to or less than the set ratio value that is the target to be reached of the irregular flow ratio.

A fuel control system obtains a measured amount of fuel consumed by an engine and one or more corresponding operating parameters of the engine and determines a fuel consumption modeled amount based at least in part on a fuel consumption model of the engine and the one or more operating parameters. The fuel consumption model associates different amounts of fuel that, when supplied to the engine, generate corresponding designated outputs of the engine. The system also determines one or more differentials between the measured amount of fuel and the modeled amount and, responsive to the one or more of the differentials exceeding a threshold value, the system identifies one or more components of the powered system that contribute or cause the one or more differentials and/or changes an amount of fuel supplied to the engine according to the fuel consumption model to obtain a desired output of the engine.

A vehicle control system as described herein can include one or more processors that can identify one or more geographic areas through which a vehicle group is scheduled to travel for an upcoming trip. This area or these areas may be identified as area(s) where there is an increased likelihood of a need for derating one or more engines of the vehicle group. The processor(s) can create or modify a trip plan that dictates one or more operational settings of the vehicle group for one or more of different locations, distances, or times of the upcoming trip. The processor(s) may create or modify the trip plan to avoid a decrease in total power output from the vehicle group within the geographic area(s).

Methods and systems are provided for boosted engines. In one example, a method for a boosted engine method may include storing compressed air in a reservoir for supply to the engine during increased engine load operating conditions and replenishing the air in response to pressure dropping below a nominal threshold; and increasing the pressure beyond the nominal threshold in response to increased temperature of the stored air in the reservoir even when operating conditions include decreased engine load, and purging the increased temperature stored air to bring pressure back down toward the nominal threshold. In one example, increasing pressure to the reservoir may include supplying compressed air from an air suspension system. In one example, increasing pressure to the reservoir may include supplying compressed air from an air compressor separate from an engine turbocharger compressor. In one example, the method may include, in response to a vehicle operator tip-in during the increasing of the pressure beyond the nominal threshold, simultaneously supplying stored compressed air to the engine while replenishing the air.

Various methods and systems are provided for controlling emissions. In one example, a controller is configured to respond to one or more of intake manifold air temperature (MAT), intake air flow rate, or a sensed or estimated intake oxygen fraction by changing an exhaust gas recirculation (EGR) amount to maintain particulate matter (PM) and NOx within a range, and then further adjusting the EGR amount based on NOx sensor feedback.